ITBM-RBM最新文献

Heart surgery has been performed in an increasing number of elderly patients in the recent years. Currently about 20 % of all patients in cardiac surgery are older than 80 years, and their number is increasing constantly. Valve replacement (mainly aortic), coronary artery bypass grafting or combined approaches are the most common procedures in the elderly. However, aortic surgery is extending progressively regarding the improvement of the preoperative conditions of the patients. The adjunctions of endovascular therapies have opened the field for the treatment of complicated pathologies of the descending aorta with a lower morbidity. Nevertheless, if the technical conditions are similar to young persons, the main difference is the absence of postoperative alternative in case of complications.

Objective. —

Continuous renal replacement therapy (CRRT) is widely used in the management of septic patient with acute renal failure (ARF). Short filter lifespan (<24h) is a major concern and could result of a procoagulating state. The aim of this work is to study the relationship between antithrombin (AT) deficit and early filter clotting, and whether supplementation of AT could increase filter lifespan. We also compare two different methods for supplementation : Bolus Vs Continuous Infusion.

Design and Setting. —

The authors conducted a two center prospective study from March 2003 till May 2004. Patients: Twenty-seven patients in septic shock and ARF were included and treated by CRRT. Unfractionned heparin (UHF) was used for anticoagulation. Supplementation was started after two early filters's clotting with the two different methods. Measurements and main results: The level of AT was measured before CRRT and every day. The risk of thromboses increases dramatically at a threshold rate of 60 %. Supplementation allows a longer filter lifespan (15,2 h to 33,2h). Continuous infusion allows better

Results. —

48,5 h vs. 27,8 h for bolus method. The loglinear regression with frailty is statistically significant shows a high correlation between filter lifespan logarithm and AT level (P<0,00I )

Conclusion. —

This study shows that a level of AT under 60 % increases the risk of early filter clotting. A supplementation of AT could increase the filter lifespan by more than 100 %. Continuous infusion should be preferred. Cost effectiveness should be evaluated shortly.

L'augmentation des interventions de chirurgie cardiaque chez l'octogénaire est due au vieillissement de la population qui présente davantage de valvulopathies dites ≪dégénératives≫, en particulier rétrécissement aortique et régurgitation mitrale. Les comorbidités préopératoires sont souvent liées à l'athérome. La présence d'une broncho-pneumopathie chronique obstructive, une diminution de la clairance de la créatinine ou un score de Parsonnet élevé sont des éléments de mauvais pronostic. La gestion des médicaments cardiovasculaires préopératoires et de l'anesthésie doit être adaptée à l'âge pour éviter les hypotensions artérielles périopératoires. La fréquence plus élevée de complications postopératoires cardiovasculaires (bas débit cardiaque), des troubles rythmiques, des complications rénales, neurologiques et infectieuses explique l'augmentation de la durée de séjour et da la mortalité. La qualité de vie dans les mois suivants est peu différente de celle des patients plus jeunes opérés. Une évaluation soigneuse et une information du patient et de ses proches apparaissent donc indispensables avant la chirurgie cardiaque chez l'octogénaire.

The increasing rate of octogenarians operated on in cardiac surgery is due to the aging of population who is more affected by “degenerative valvulopathies”, particularly aortic stenosis and mitral regurgitation. Preoperative comorbidities are often linked with atherosclerosis. The presence of chronic obstructive bronchopneumopathy, deacreased creatinine clearance or high Parsonnet score predict a poor outcome. The preoperative prescription of cardiovascular drugs and anaesthesia should aim at avoiding hypotension. The increased incidence of postoperative cardiovascular (low cardiac output), rhythmic, renal, neurologic and infectious complications explains the increased length of stay and mortality. However the quality of life during the following months is not more affected than in younger patients. A careful preoperative evaluation and patient's information appear mandatory before cardiac surgery in octogenarians.

Quatre-vingt-huit patients octogénaires opérés de pontages coronaires ont été comparés à 165 patients âgés de 60 à 70 ans, après appariement selon les principaux facteurs de risque. La mortalité opératoire n'était pas différente entre les deux groupes. La survie à long terme des octogénaires était inférieure mais supérieure à celle de la population française du même âge.

We compared 88 octogenarians who had a coronary surgery with 165 patients aged between 60 and 70, the two groups having been paired according to the main risk factors. Operative mortality was similar in both groups. Long-term survival was lower for the octogenarians but higher than for the same age French population.

Post cardiotomy circulatory support is mainly a bridge to recovery. French law indicate the necessity to have an available device, but the choice depends of experience and risk/benefit of transportation to a transplant center and bridge to bridge. Time to recovery is dependant of unloading, but results seem to be better after ECMO in case of pediatrics and cardiac transplant graft failure. ICU problems include frequent renal failure, multi-organ dysfunction related to SIRS, and hemorragic risk. Pulmonary hyertension is now easily controlled by inhaled NO. Nevertheless, global mortality is usualy higher (>60 %) than in bridge to transplant. Indication of post operative assistance should prevent these complications and need a rapid decision. In case of delay, biventricular assistance is required. New devices using axial non pulsatile flow are under trail in mitral surgery.

Le facteur VIIa recombinant peut être salvateur en cas d'hémorragie menaçant le pronostic vital après chirurgie cardiaque. Nous commentons les données de la littérature à ce propos et donnons quelques indications sur notre expérience. Nous présentons 1'observatoire en cours en France sur ce sujet.

Recombinant coagulation factor Vlla can be useful in exsanguinating patients after cardiac surgery with cardiopulmonary bypass. There is an ongoing French registry on this topic.

Tranexamic acid, a synthetic lysine analogue, is an indirect anti fibrinolytic agent. It acts by plasminogene transformation in inactive plasmin.Usual posology is 10 mg/kg loading dose followed by a continuous perfusion of I mg/kg/min during 10 hours or more simply, with an equivalence of effect, two direct intravenous injections of 15 mg/kg, one before the surgical incision, the other after the injection of prolamine. Four meta analyses compare tranexamic acid with aprotinine in cardiac surgery with cardio pulmonary bypass. One meta analysis studies the effect of the acid tranexamic in off-pump coronary artery bypass grafting. Three observational studies bring back the effects of tranexamic acid use in cardiac surgery. These studies show a fall of the post operative bleeding, with reduction in the blood exposure and a less percentage of patients returning to theatre for exploration for bleeding among patients treated by the acid tranexamic compared to patients untreated by an anti fibrinolytic agent. Compared to these 3 items (bleeding, transfusion, Re immediate operation) the results are equivalent to those obtained with the aprotinine. An increased risk of arterial or venous thrombosis was not shown in these studies. The tranexamic acid does not have an anti inflammatory action. The indirect action of the acid tranexamic does not ensure a maximum effectiveness in the cases which active plasmine is already circulating in pre the operative period (dissection, fissuration, rupture of aorta) Tranexamic acid has very few or no side effect. Its cost is modest. It is effective on the post operative reduction of blood requirements after cardiac surgery.

The authors have evaluated a new hollow fiber membrane oxygenator specially dedicated for neonatal cardiac surgery. The priming volume is optimized at 31 ml with a membrane surface area of 0.22 m2 for a maximum blood fow 0.71/min. The main finding of this evaluation is the ease with wick the management of blood gaz is possible. This new oxygenator allows to avoid hypocarbia and hyperoxia often observed during neonatal cardiopulmonary bypass.